The present invention relates to a swash plate type compressor and particularly to a swash plate type compressor for use in air conditioning systems for vehicles.
Conventionally, in the swash plate type compressor of this type, the sliding portions thereof are lubricated by circulating refrigerant gas containing lubricating oil which is introduced from an outer refrigeration cycle into a swash plate chamber.
In the swash plate type compressor of this type, a suction passage is perforated within a space between adjacent cylinder bores which are perforated in a combined cylinder block to communicate the swash plate chamber with suction chambers perforated in housings which are fixed to both ends of the combined cylinder block.
However, as the smaller-sized compressor is required, and as the number of the cylinder bores is increased, it has become difficult to obtain a space large enough for perforating the suction passage having a sufficiently large cross-sectional area.
In order to solve the above problem, in each of all spaces between adjacent cylinder bores, a suction passage is perforated.
However, in the compressor having a plurality of suction passages, the liquid refrigerant and liquid oil separated from the refrigerant gas stays in the bottom portion of the swash plate chamber and is supplied from the suction passage positioned in the bottom portion thereof into the suction chamber, and then the liquid refrigerant and liquid oil is sucked into the cylinder bores. Therefore, when the piston 11 is reciprocated, liquid compression occurs within each of the cylinder bores. As a result, in the conventional compressor, parts of the compressor and the pipes positioned outside the compressor communicated thereto are in danger of damage.
And conventionally, when a large number of the cylinder bores is provided in order to make the compressor small and light, an exhaust chamber is disposed near the radially central portion of the housing and the suction chamber is disposed along the outer periphery thereof.
However, in the compressor having the above described construction, the shaft seal chamber through which the drive shaft is inserted is separated from the suction chamber so that the shaft seal member accomodated within the shaft seal chamber is not sufficiently lubricated nor cooled.
As a result, the shaft seal member is damaged after a short period of time.
Accordingly, one object of the present invention is to provide a small sized and light swash plate type compressor, particularly a swash plate type compressor for use in air conditioning systems of a vehicle.
Another object of the present invention is to provide a swash plate type compressor having excellent durability which prevents the liquid compression from occurring in the cylinder bores and which effectively lubricates the sliding portions.